If you use this init() method, you cannot specify a service with the
name of 'ApplicationConfig' in your service manager config. This name is
reserved to hold the array from application.config.php.
The following services can only be overridden from application.config.php:
- ModuleManager
- SharedEventManager
- EventManager & Zend\EventManager\EventManagerInterface
All other services are configured after module loading, thus can be
overridden by modules.